It is possible to use the super-light method to go back to the past. When a person's speed reaches the speed of light, personal time can be stopped. At this time, other people's time still has to go. When it reaches the super-light speed, your time is still there. If you go backwards, you can reach the past. The past here belongs to the time when you came here. It contains Li Bai, Du Fu, and Jay Chou. But super-light speed is not easy to achieve. In Einstein's theory, super-light speed is impossible. However, an experiment has now confirmed the possibility of super-light speed, breaking the theory of relativity and creating a breakthrough in science. But no matter what, in speed theory, you can only go to the past, not the future. In other words, if you use speed, you can't go back after you go to the past. But there is another way to travel through time and space, which is to distort space. When the space you are in is distorted to the past or future space, a wormhole will be created, through which you can reach the past or future, and the time it takes is even shorter than the speed of light. As shown in the picture (picture made by myself). But the time and space reached in this way is different. Time and space will have multiple branches, and each branch defines a different history. In our time and space, there are Li Bai, Du Fu, and Jay Chou, but they may not be in other time and space, and they may not be in the ancient times of other time and space. During the Tang, Song, Yuan, Ming and Qing dynasties, we still have a long way to go to find the desired time and space and to have precise force parameters.